Joseph C. Meyer, Jr. doesn’t want to take this call. The 89-year-old owner of Meyer Dairy spent the day buying a new pump in Lancaster, Pa. At approximately 6:30 p.m. he pulled into the parking lot of Meyer Dairy and began checking in with his employees. Like every other day the dairy is open, he wasn’t planning on leaving until closing time — 11 p.m.

So when his office phone rings with a woman who wants to talk about eggnog for a local food column, he is frank. He doesn’t have time.

“No. No. I don’t do interviews anymore,” said Mr. Meyer, grandson of W.C. Meyer, who purchased the first Meyer farm back in 1887. “At my age, they get tiresome.”

I begged. Mr. Meyer relented.

After all, I tell him, I’m a loyal customer who faithfully purchases all my dairy products from Meyer. Our kids drink only Meyer milk. Meyer chocolate milk is a standard treat in our house. And indulging in Meyer Dairy eggnog has become one of our favorite State College Christmas traditions.

Just a few questions, I plead.

Despite his hectic day, Mr. Meyer patiently informs me that the company produces and sells 3,000 gallons of eggnog during the holiday season. Meyer Dairy began selling the drink not long after it opened its doors in 1970, he says.

Today, people come from as far as Pittsburgh to buy it, and many customers take it with them on out-of-state holiday road trips. According to Mr. Meyer, even folks in Florida will be drinking it this Christmas.

What makes Meyer eggnog different?

Mr. Meyer points to the ingredients, although he won’t provide specifics. “It’s almost top secret,” he explains. “Only the employees know.” They key ingredients, of course, are the milk and cream from Meyer’s cows.

Meyer Dairy eggnog is delectable in coffee and mixed with hot chocolate. For the ultimate holiday indulgence, I’m planning on soaking a few hearty slices of Gemelli bread in the stuff, and frying up some Eggnog French Toast. (In the caloric climb from Thanksgiving to Christmas, the Eggnog French Toast represents a precipice that can only be scaled by an experienced holiday eater.)

Despite the many delicious ways to consume Meyer eggnog, Mr. Meyer is a traditionalist who believes the drink is best straight out of the bottle — and out of reach of the rum. “Well, I think alcohol spoils the taste,” he explains, “but I guess if you like alcohol, you’ll put it in anything.”

I realize our interview will be cut short at any moment, so I try my luck with a few hasty questions.

What does he want for Christmas?

“Nothing,” he says, steering the conversation toward the people on his list, mainly his 12 great-grandchildren, including two who are on the way.

What is he thankful for?

“Everything. For pretty good health — for being alive.”

Mr. Meyer reminds me of my 97-year-old grandfather, who owned the North Jersey trucking business founded by his father. He went to work every day when he was in his 80s, too, I tell him. My grandfather started the workweek with a large bowl of fruit on his desk; by the end of the week, the apples, bananas and oranges were gone.

Mr. Meyer asks me a few questions about my grandfather and how I ended up in State College, before politely ending our conversation.

He has to get back to his pump. I can’t keep him any longer, especially if I want more eggnog.

Correction: A previous version of this story incorrectly stated the age of Joseph Meyer. He is 89.